A study of angles between major hepatic veins in human cadavers.
"In the strangely beautiful dynamism of embryology, the liver appears as a tree that grows out of the virgin land of foregut in order to increase its metabolic and digestive function". (6)
INTRODUCTION: The liver is the largest gland in the body which performs an astonishingly large number of tasks that impact all body systems. One consequence of this complexity is that hepatic disease has widespread effects on virtually all other organ systems. Understanding function and dysfunction of the liver, more than most other organs, depends on understanding its structure. The major aspects of hepatic structure that require detailed attention include:
The Hepatic Vascular System: It has several unique characteristics relative to other organs. Resection of the liver was started only at the beginning of the 18th century. In 1716, G. Berta performed the first partial liver excision. However, due to unstoppable bleeding and high mortality, surgeons feared to operate on this organ. Only in 1874, C. Langenbuch reported the first successful liver resection. (7)
Today, these procedures are performed not only for treatment of acute emergencies (e.g., traumatic injuries or abscesses) but also as potentially curative therapy for a variety of benign and malignant hepatic lesions.
Progress of diagnostic human's liver imaging (ultrasound, computerized tomography, magnetic nuclear resonance, etc.) stimulates development of modern liver surgery. Therefore, before and during the operation, surgeons and radiologists can determine the site and extent of liver damage, its relationship with blood vessels and ascertain which part of the liver should be resected.
For this reason, physicians have to know anatomical and clinical peculiarities of the liver. (1)
In spite of the remarkable standardization of the technique involved in this procedure, the operation remains a formidable technical challenge.
This study would thus, enable the surgeons to perform life-saving surgeries like Living-related liver transplantation and management of liver related injuries in trauma.
MATERIALS AND METHODS: The study was conducted in the Department of Anatomy, Dayanand Medical College and Hospital, Ludhiana, Punjab and Adesh Institute of Medical Sciences & Research, Bathinda, Punjab, after the approval by the Hospital Ethics Committee.
The study was done on 60 specimens of liver from embalmed, apparently disease free adult cadavers, in the Department of Anatomy, Dayanand Medical College and Hospital, Ludhiana and Adesh Institute of Medical Sciences & Research, Bathinda, Punjab.
1. To begin with, the hepatic veins of the livers were cleaned. They were thoroughly washed with water, followed by normal saline. Suction machine was used to take out any remaining clots. This was done, till saline ran from the veins.
2. To put the liver in anatomical position, wooden stand which had a long and tapering wooden stick, fixed to a plain wooden platform was taken. A wooden stand was used as it hardly causes any shadow on X-ray films. The liver was placed on the wooden stand in such a way that the long stick of the stand was introduced into the inferior vena cava. Thus, liver stood independently on the stand with inferior vena cava vertical (as shown in the photograph).
A freshly prepared emulsion of 125 gm of barium sulfate mixed in 180 ml of water was used. The consistency of emulsion was such that it was neither too thin nor too thick.
1. A 200cc syringe was used to fill major hepatic veins with emulsion.
2. Barium sulphate emulsion took 15-20 minutes to gravitate slowly down the veins and its tributaries. After this time-interval, the cephalic portion of the hepatic veins became empty and this was refilled. The extra amount was cleaned with wet cotton to avoid any unwanted shadow on X-ray films.
3. The X-rays were taken in different views. The machine was movable and the stand with liver was stationary. The different views were:
1. Antero-posterior view
2. Supero-inferior view
3. Right lateral view
The following parameters were studied in the radiographs:
a. Angle between right and middle hepatic vein.
b. Angle between middle and left hepatic vein.
The livers were subsequently dissected under bright illumination.
Using X-rays as a rough guide, the dissection was started along the Cantlie's line for middle hepatic vein.
Gross angles between the right and middle hepatic vein and middle and left hepatic vein was measured after putting thin iron wires (0.960 mm calibre) along the medial edge of the vein, up to a distance of 2.5 cm. The angles were measured using goniometer. The wires were non-malleable and non-ductile to prevent errors in measurement.
The observations were then tabulated and analyzed using appropriate statistical methods.
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Fig. 8: According to the mathematical principle of diagonal equation Angle A=Angle B. IVC-inferior vena cava; MHV-middle hepatic vein; LHV-left hepatic vein; RHV-right hepatic vein.
[FIGURE 8 OMITTED]
Fig. 9: Axial diagram of the liver at the level of the confluence of the hepatic veins shows the dotted lines drawn from the confluence of the middle hepatic vein (MHV) or right hepatic vein (RHV) and the IVC straight through each hepatic vein. These lines indicate the imaginary boundary, which are considered to be the longitudinal scissurae. (11)
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RESULTS: Angle between middle and right hepatic veins were measured. Mean on dissection was 31.857 [+ or -] 8.996 and on X-rays, was 26[degrees] [+ or -] 11.97[degrees]. Angle between middle and left hepatic veins were measured.
Mean on dissection was 74.0 [+ or -] 19.383, on X-rays was 41.267[degrees] [+ or -] 11.97[degrees] The angles between right and middle hepatic veins and the angles between middle and left hepatic veins were acute in most of the cases. Only in one liver the angle between right & middle hepatic vein was 130 degrees in gross. In one liver, the angle between the major veins could not be measured. This was so because of the alignment of the veins was such that they overlapped.
DISCUSSION: The results corresponded to some extent with those of Shao et al (8). He did not measure the angles between the middle and right hepatic veins. The angle between the middle and right vein, in present study, ranged from 20-45[degrees] (mean 31.857 [+ or -] 8.996). No reference was found regarding this parameter.
Segall (9) stated that the angles formed by the junctions of the larger vessels are acute (15o 40o). No specification is made regarding the names of the vessels.
Peschaud et al (10) has reported that the right hepatic vein entered the vena cava at an acute angle in 100% cases.
The angle between right hepatic vein and inferior vena cava was not measured in the present study.
CONCLUSION: Liver is a complicated organ. Naming of the parts of this complex inner organ is still highly varied: parts, halves, lobes, divisions, sectors, segments, and sub-segments.
Our understanding and explanation of liver composition are still defined differently among anatomists, surgeons, and radiologists, thus not only confusing less experienced specialists, but also increasing probability of mistakes.
The prognosis of patients not only is dependent upon timely management but also the precise knowledge of position and architecture of hepatic veins. This study would help the surgeons to access the area and control the hemorrhage. These are the major problems confronting the surgeon undertaking the removal of hepatic tumours and cysts.
It should be kept in mind that the present study had a smaller number of livers so, it is worthwhile to perform a similar study on more number of livers for its theoretical and practical importance in coming years.
(1.) Bismuth H. Surgical anatomy and anatomical surgery of the liver. In: Blumgart LH, editor. Surgery of the liver and biliary tract [CD-ROM]. Edinburgh (UK): Churchill Livingstone; 1994.
(2.) Clifford S. Cho, MD, James Park, Yuman Fong, Hepatic Resection(23), Section 5 Gastrointestinal Tract and Abdomen
(3.) Andrei C. Stieber, J. Wallis Marsh, Thomas E. Starzl, Preservation of retrohepatic vena cava during recipient Hepatectomy for orthotopic transplantation of the liver. Surgery Gynaecology & Obstetrics, June 1989 VOLUME 168. NUMBER 6
(4.) Peschaud F, Laforest A, Allard MA, El Hajjam M, Nordlinger B. Can the left hepatic vein always be safely selectively clamped during hepatectomy? The contribution of anatomy. Surg Radiol Anat. 2009 Nov; 31(9):657-63.
(5.) Saulius Rutkauskas, Vytautas Gedrimas, Juozas Pundzius et al. Medicina (Kaunas) 2006; 42(2)
(6.) R Selzer as quoted in Skandalakis J E, Skandalakis L J, Skandalakis P N, Mirilas P. Surgical Clinics of North America. 2004; 84: 413.
(7.) JE. Hepatic surgery and hepatic surgical anatomy: historical partners in progress. World J Surg 1997; 21:330-42.
(8.) Shao C X, Zhang T, Zhu J D, Meng W C S. Left hepatic vein: can be sutured and ligated blindly in left hepatectomy? Hepatobiliary and Pancreat Dis Int 2004; 2 (3): 371-373.
(9.) Segall H N. An experimental anatomical investigation of the blood and bile channels of liver. Surgery, Gynecology and Obstetrics 1923; 37: 152-178.
(10.) Peschaud F, Benoist S, Penna C, Bernard N. Anatomical basis for clamping of the right hepatic vein outside the liver during right hepatectomy. Journal Surgical and Radiologic Anatomy. 2006; 28(6): 625-630.
(11.) Ohashi I, Ina H, Okada Y, Yoshida T, Gomi N, Himeno Y, Hanafusa K, Shibuya H. Segmental anatomy of the liver under the right diaphragmatic dome: evaluation with axial CT. Radiology 1996; 200: 779-783
[1.] Daizy Singh
[2.] Sandeep Singh
[3.] Poonam Singh
[4.] Ritu S. Chowdhry
[5.] Paramjit S. Chowdhry
PARTICULARS OF CONTRIBUTORS:
[1.] Associate Professor, Department of Anatomy, Adesh Institute of Medical Sciences & Research, Bathinda.
[2.] Assistant Professor, Department of Radiology, Adesh Institute of Medical Sciences & Research, Bathinda.
[3.] Professor and HOD, Department of Anatomy, Dayanand Medical College & Hospital, Ludhiana.
[4.] Adjunct Professor, Department of Anatomy, Medgar Ever's College, CUNY, USA.
[5.] Adjunct Faculty, Department of Medicine, Kaplan, New Jersey, USA.
NAME ADDRESS EMAIL ID OF THE CORRESPONDING AUTHOR:
Daizy Singh, #111, New Lajpat Nagar, Pakhowal Road, Ludhiana, Punjab.
Date of Submission: 29/04/2014. Date of Peer Review: 30/04/2014. Date of Acceptance: 21/05/2014. Date of Publishing: 31/05/2014.
Table 1: Comparison of angles of present study with those of previous studies Author Year Between left and middle hepatic vein Shao et al 2003 65-115 (91 [+ or -] 18.3[degrees]) Present Study 65-130[degrees] (74 [+ or -] 19.383) Dissection Radiology 15-70[degrees] (41.267 [+ or -] 11.97[degrees]) Author Between middle and right hepatic vein Shao et al -- Present Study 20-45[degrees] (31.857 [+ or -] 8.996) Dissection Radiology 5[degrees]-45[degrees] (26.0 [+ or -] 11.970)
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|Title Annotation:||ORIGINAL ARTICLE|
|Author:||Singh, Daizy; Singh, Sandeep; Singh, Poonam; Chowdhry, Ritu S.; Chowdhry, Paramjit S.|
|Publication:||Journal of Evolution of Medical and Dental Sciences|
|Date:||Jun 2, 2014|
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